Hammer-mill mixer combination



Filed Dec. 31, 1940 F jE-l- BY QM/W A TTOPNEX Patented Nov. 2, 1943 UNITED STATES PATENT OFFICE? HAMMERJHLL IVHXER COMBINATION Harry H. Harris,- Palo Alto, Calif assignor to Enterprise Engine & Foundry Company, San Francisco, Calif., a corporation of'Californial' Application December 31, 1940; serial-1N0. 3'7 2;619"" ('Cl. sc -1' 1) 5 Claims.

This invention relates to vertical hammer mills or'disintegrators and the inventionhas for its object improvements whereby the mixing of various modifying agents withthe disintegrated material A is facilitated.

Other advantages of the improved'construction will appear in the following description and accompanying drawing.

In the drawing:

Fig. 1 is a vertical section of themill showing all-of its main parts andthe relation of my improvement thereto.

Fig; 2 is-afragmentary cross section of Fig. 1 taken along the line 2'-2 of Fig. 1.

Briefly described, my improvement in a vertical hammer mill comprises extending the rotor shaft downward below the lowest bearing through aspecial receiving chamber for the disintegrated product of the mill, and providing extra mixing blades on the shaft within the re ceiving chamber, and means for introducing extraneous'materials to the chamber for mixing with the disintegrated ands'creened product from the mill rotor, so as to produce any desired blended product before finallydischarging the material. As a further feature an exhaust fan or pump'may be connected to the lower end of the rotor shaft to forcibly discharge the blended or mixed product.

In the drawing the vertical hammer mill comprises the old and well known features of a frame I having an outwardly'projecting circular supporting flange 2 with belt holes 3 for securing. it to a foundation, while at the upper end the frame is of reduced diameter as at I, secured to the upper end of'which is a spacing frame 4, in turn supporting a motor 5, the shaft 6 of which is coupled at 'I' to the rotor shaft 8 of the mill; The rotar shaft extends downwardly through a cylindrical chamber formed by curved screen sections 9, and the shaft is rotatablypositioned in bearings Ill and II, the latter of which preferably supports the weight of the shaft, and is supported byribs" or spider arms I 2-extending; radially from a circular flange I3"in turn supported within a circular flange I4 connected to frame I by radially extendingv ribs or spider arms I5.

The mill frame I includes vertical members I5 spaced outwardly from the screen shell 9 and around which members is a sheet metal enclosing casing llmade in two-or more'sections and clamped in-place a-roundthe mill as by pivot" bolts lfl 'and wing nuts I9'as best's1iown in Pig;-

2,- or otherwise removablysecured orhinged thereto.

Within the screen chamber the sha'ft B- is provided-with the usual beaterarms or so-called hammers 20: which project radially from the shaft, or rather fro'nfahub or hub sections 2 I suitably secured-- to thesha'f-t, and which beater arms'may 'be-ofi any shapejsize, or lengthg-fixed or pivotally-mounted; and in any: desired arrangement; as commonlyused in mills of this-typefor beating and disintegrating material fed into'the upper end o f the. screen chamber froin a feed chute 2 2, so -th'at by" the rapid. revolution of the beater arms the material isbroken up or dis-- integrated toan extent'dependiiig on thefnature of the material, the'shapatlength"and sp'ee'dof the heaters. The finely divided: material" is thrown through the openings in the screen shell 9 'surroundingithe rotor and; together with the remainder of the" finely divided material which passes through a horizontally. disposed screen 23 which extends across the"rotorchamber beneath the lowest' beater arm, all falls in direction ofthe arrows'into a conical receiver 24"secured-'to the bottom of the frame flange 2 as by bolts-25- and 'to the lower conical endof which receiver a horizontally positioned ejecting fan or- 'cen trifugal punt-1y 26 f is secured-ism) as=to 'receive: all of the material from the receiver '24 for ejection from the pump outlet 2-7 as indicatedby the" horizontal arrow toany .point'desired.

The ejectihgpumpsor vfain'fis; of 'the' conventional I type and is conveniently; driven by; the lower end of the rotor shaft 8 which mayabe additiomally supported'by'a-bearin'g .SII at the lower end" of-the conical receiver 24' if desired. The conical' receiver assures :all' of thema-terial from the 'mill convergingand: falling into" the fan.- Between the "andthe screehs through' whicli the dis integratedinaterial falls-are sever fag-arms 2 proj ecting from' the shaft "formix ing with the disintegrated 'inateri'alah ous materialseitheripowdered -orliquid, or which requiresome' disintegration; as maybe in troduced into the receiver 24-througha-secondary fee'ol chute "29 entering the base of 'th'e mill-frame just above the receiver 2 4; and whichextraneou s ma terial's' may b'e'- introduced bymeans of any desired feedcohtroll'ing means [not shown;

As-mixirig a rms 'is trav'el at a high rate of speed, their normal ten'dency 'tdlift thematenai in receiver 2'4 to the largestdiameter of there ceiver is' overc'omebyhaving'them relatively-har row in vertical cross section and sl igl'ltly slanted (propeller-like) as indicated at 28 'so' tha't a slight tendency to force the materials downwardly will result, so that they will all fall readily into the pump inlet after thorough mixing.

This general type of vertical hammer mill with both cylindrical screen surrounding the rotor as well as fiat screen across the lower end of the rotor chamber, also a receiver below and discharge pump, is shown in prior Patent #1,977,771 and likewise the general features in numerous other prior art patents, but the provision for introduction of extraneous materials to the disintegrated material and supplementary mixing blades carried by the rotor shaft all in a supplementary mixing chamber below the disintegrating chamber at a point preceding the discharge pump inlet, I believe to be new, and I therefore claim:

1. In a vertical hammer mill having a rotor mounted on a vertical shaft with laterally extending hammers revolvable within a vertically positioned cylindrical screen, and a mill casing or outer wall surrounding and spaced outwardly from the screen whereby material fed into the upper end of the cylindrical screen will be disintegrated by the revolving hammers and hurled through the screen to fall from the lower end of the space between the screen and the mill casing, the improvement which comprises a hollow receptacle below said screen and said space between the screen and the mill casing and forming a continuation of said casing so as to receive the disintegrated and screened material falling from said space an outlet in the bottom of the receptacle, said vertical shaft of the rotor extended downwardly into saidreceptacle and terminating adjacent the outlet in the bottom thereof, mixing blades in said receptacle carried by the extended shaft and arranged to thoroughly mix the disintegrated and screened material as it falls from said space, means for introducing extraneous material into the upper portion of said receptacle for simultaneously mixing with said disintegrated and screened material, and a fan on the lower end of the vertical shaft for passing the mixed materials from the outlet inv said receptacle.

2. In a vertical hammer mill having a rotor mounted on a vertical shaft with laterally extending hammers revolvable within a vertically positioned cylindrical screen, and a mill casing. or outer wall surrounding and spaced outwardly from the screen whereby material fed into the.

upper end of the cylindrical screen will be disintegrated by the revolving hammers and hurled through the screen to fall from the lower end of the space between the screen and the'mill casing, the improvement which comprises a hollow receptacle below said screen and said space between the screen and the mill casing and forming a continuation of said casing so as to. receive the disintegrated and screened material falling from said space a cylindrical housing at the lower end of the receptacle, a discharge opening in said housing, said vertical shaft of the rotor extended downwardly into said receptacle and terminating within the cylindrical housing, mixing blades in said receptacle carried by the extended shaft arranged to thoroughly mix the disintegrated and screened material as it passes through the receptacle, means for introducing extraneous material into the upper portion of said receptacle for simultaneously 'mixing with said disintegrated and screened material, and a fan within the cylindrical housing and attached to the lower end on the Vertical shaft for passing the mixed materials through the discharge opening in said housing, said mixing blades formed with angular lower faces tending to urge the mixed material toward the discharge opening.

3. In a vertical hammer mill having a rotor mounted on a vertical shaft with laterally extending hammers revolvable within a vertically positioned cylindrical screen, and a mill casing or outer wall surrounding and spaced outwardly from the screen whereby material fed into the upper end of the cylindrical screen will be disintegrated by the revolving hammers and hurled through the screen to fall from the lower end of the space between the screen and the mill casing, the improvement which comprises providing a hollow receptacle below said screen and said space between the screen and the mill casing and forming a closed continuation of said casing so as to receive the disintegrated and screened material falling from said space, said vertical shaft of the rotor extended downwardly into said receptacle, mixing blades in said receptacle carried by the extended shaft arranged to thor-- oughly mix the disintegrated and screened material as it falls from said space, and means-for I introducing extraneous material into the upper portion of said receptacle for simultaneously mixing with said disintegrated and screened material, and means for passing the mixed materials from a common outlet at the bottom of said receptacle, said mixing blades formed with angular faces tending to urge the mixed material toward said outlet, said receptacle being conical with its smaller end directed downwardly, and said mixing blades being in several rows one below the other and of decreasing length toward the lower end of the receptacle to slow up the rotary motion of the material.

4. In a vertical hammer mill having a rotor mounted on a vertical shaft with laterally extending hammersrevolvable within a vertically positioned cylindrical screen, and a mill casing I or outer wall surrounding and spaced outwardly from the screen whereby material fed into'fthe upper end, of the cylindrical screen will be disintegrated by the revolving hammers and hurled between the screen and the mill casing and forming a closed continuation of said casing so as to receive the disintegrated and screened material falling from said space, said vertical shaft of the rotor extended downwardly into said receptacle, mixing blades in said receptacle carried by the extended shaft arranged to thoroughly mix the disintegrated and screened material as it falls from said space, an inlet conduit at the upper part of said receptacle adapted for feeding ex-.

traneous materials into said receptacle for simul-" taneous mixing with said disintegrated and screened material, said receptacle being'conical with its small end directed downwardly and pro- 5. In a vertical hammer mill of the character described, means forming a chamber" at the bottom of the mill arrangedto receive the disinte-c grated material, the rotor shaft ';of the hammer mill being extended downwardly into said cham:

ber, mixing blades secured to said shaft in said 5 l chamber arranged to mix the disintegrated material received from the mill, and means for feeding extraneous materials to said chamber for mixing with said disintegrated material, said chamber being conical with its smaller end directed downwardly and provided with a discharge opening at its lower end, and said mixin blades formed with angular faces tending to urge the mixed materials toward said opening, and a centrifugal discharge fan secured across said opening to receive the materials urged toward it by said blades.

HARRY H. HARRIS. 

